The Bald Penguin (Aquanhelo calvus), is a descendant of the Little Penguin, inhabiting the earth 50 million years from now. It has evolved sufficiently so that it is different enough from the Little Penguin to warrant a new genus, Aquanhelo, in which all penguin species are able to breathe underwater. Aquanhelo is a composite of the Latin words aqua, meaning water, and anhelo, meaning breathe. Calvus is Latin for bald. Therefore the Aquanhelo calvus is literally a bald, water-breathing penguin.
The habitat of the Bald Penguin is much warmer than the habitat of its ancestor, the Little Penguin. In part, this is because of Australia's gradual drift northwards. The map on the left shows the likely location of the continents in 50 million year's time. In analysing the map, one can tell that Australia has moved northwards slightly, and collided with the archipelago of Indonesia. This closer location to the equator, combined with the greenhouse effect, means that Australia's temperatures will be slightly, if not significantly, higher.
Also, the Bald Penguin inhabits the tropical areas of what is currently Australia, Papua New Guinea, and Indonesia, as shown on the distribution map. Hence, the habitat of the Bald Penguin is hot and humid, with average temperatures around 37 degrees Celsius. There is frequent rain and occasional typhoons. During typhoons, the Bald Penguin takes shelter in its burrow. The risk of earthquakes and tsunamis are ever-present, due to Indonesia's location on a fault line.
The tropics, and especially the rainforest, are famous for their variety of life, and this would mean an increased amount of predators for the Bald Penguin. Some examples of predators are the descendants of snakes and the descendants of the komodo dragon. Dogs and cats also continue to threaten some colonies closer to urban areas. However, almost all of the Bald Penguin's predators live on land, as the Bald Penguin, like all penguins, are significantly less agile on land than they are in the water. All in all, this means the Bald Penguin lives in a more dangerous environment than the Little Penguin did.
The Bald Penguin continues to spend the daylight hours in the sea. The oceans of the tropics are filled with warm sea currents and plenty colourful fish. Water visibility is good, allowing the Bald penguin to easily catch its prey, fish and squid. These animals thrive in the tropics, and thus the Bald Penguin also thrives. The environment of the Bald Penguin brings it into contact with quite different animals from the ones the Little Penguin encountered. These might include the descendant of the green sea turtle and the descendant of the bellybutton nautilus. The Bald Penguin is found in tropical waters only, as it cannot withstand colder waters because of its lack of feathers.
Because of the increased number of predators associated with the rainforest environment, and the penguin's lack of agility on land, the Bald Penguin seeks to limit the time it spends on land. Therefore, the only times an adult Bald Penguin sets foot on land is to mate, or to sleep. Burrows are constructed in the sand, on the sides of cliffs, or in the undergrowth of the rainforest. These are all constructed as close to the shore as possible. Unlike their predecessors, the Bald Penguins can no longer afford a longer walk to their burrows. The Bald Penguin lives in colonies, with penguins from the same colony building burrows in the same area.
Structural Adaptations
Gill-type lungs A structural adaptation which separates the Aquanhelo genus from all other penguin genera is its gill-type lungs.
All penguin species in the 21st century already have a complex respiratory system, in which the air is able to travel in a circular fashion through the lungs and various sacs, as opposed to the in and out method seen in human lungs. This allows current penguins to extract as much oxygen as possible from the air, and is capable of extracting and storing massive amounts of oxygen.
Aquanhelo's lungs differ from modern-day penguin's lungs in that the inside of Aquanhelo's lungs and sacs is covered with many folded layers of tissue, looking much like a gill.
The reason why 21st century penguins (and various other animals, including humans) cannot breathe underwater is simply that the surface area of their lungs is not large enough to take in sufficient oxygen, as there is 20 times more oxygen in air than in water. However, the folded tissue in Aquanhelo's lungs and sacs give the penguin's lungs a very large surface area.
This large surface area, combined with the modern-day penguin's already advanced respiratory system means that Aquanhelo penguins are able to extract enough dissolved oxygen from water to fulfil their daily activities. Essentially, the gill-types lungs allow Aquanhelo penguins to breathe water. However, Aquanhelo penguins also retain their ability to breathe air, as their gill-type lungs are able to extract oxygen from both air and water.
Gill-type lungs is a useful adaptation for the Bald Penguin because it allows the penguin to breathe water, eliminating the need to porpoise (jump out of the water to breathe, much like dolphins or porpoises do) as the Little Penguin did. Porpoising is an activity which requires a high amount of energy, and being able to not porpoise means that the Bald Penguin is able to conserve this energy, and is therefore able to swim further, faster, deeper, and stay underwater for longer periods of time. This in turn means that the Bald Penguin is able to catch more prey than its predecessors, helping it to survive. Also, the added energy may prove useful to the Bald Penguin in escaping speedily from predators. Furthermore, in a situation that the Little Penguin was running out of oxygen, but just spied a school of fish, the Little Penguin would have no choice but to return to the surface. However, the Bald Penguin would be free to pursue the fish. This would also contribute to the Bald Penguin being able to catch more prey. An environmental pressure leading to this adaptation was the amount of time penguins spent in the sea- for hours on end, every day. In fact, the Bald Penguin probably spends more than half their life in the water. Constant porpoising to breathe is exhausting work, so the Bald Penguin developed gill-type lungs to survive in an environment where every ounce of energy is needed.
No feathers
A second structural adaptation of the Bald Penguin is its state of featherless-ness, or baldness. The featherless-ness of the Bald Penguin contributes to both its common name ("Bald" penguin) and it's Latin name (calvus is Latin for bald). This is a useful adaptation to the Bald Penguin because it prevents the penguin from overheating. The feathers of previous penguins, like the Little Penguin, had very downy bases, are unsuitable for warmer climates. In fact, there have been cases of penguins overheating on warm summer days in Antarctica, panting and lying down on the ice to try to escape the heat. If a penguin's feathers are unsuitable for a warm Antarctican day, they are definitely unsuitable for life in the tropics. The fact that the Bald Penguin is featherless means that it retains less heat, and it is easier for the Bald Penguin to cool off, thus preventing overheating. The feathers of a penguin also prevent water from reaching the penguin's skin. However, the Bald Penguin's skin is in direct contact with the water, which also helps the Bald Penguin to remain cool. Instead of feathers, the Bald Penguin's skin is much like a dolphin's, and retains the penguin's distinctive countershading (dark dorsum and light belly). The state of featherless-ness might also allow the Bald Penguin to swim faster, as, despite their waterproof-ness, the feathers of the Little Penguin might have caused the penguin some drag. The environmental pressure leading to this adaptation is the heat of the tropics, which meant that the Bald Penguin no longer needed feathers to stay warm, and is in fact in more of a danger of overheating.
Behavioural Adaptation
Scouting the shore
A behavioural adaptation of the Bald Penguin is the way they come ashore after spending a day at sea. Instead of simply waddling onto land in a group like the Little Penguin did, an entire colony of Bald Penguins congregate underwater not far from the shore. They then send two or three scouts ashore at various points of the coast. The scouts are normally slightly older penguins who have gone through at least one, more likely two or three breeding seasons. The scouts would check for predators, before calling the 'all clear' to their peers in the water, signalling that it is safe to come ashore. What follows is a mad dash by large groups of penguins to get to their burrows as fast as possible. If the all clear is not given, the colony of Bald Penguins can stay underwater all night waiting, if necessary. This is useful to the Bald Penguins because it allows them to avoid predators whenever possible, thus ensuring that the colony is not wiped out as they come ashore. The sending of scouts also allows them to minimize any damage to the colony, should there be a predator waiting for them, as only the scout would be in any danger. An environmental pressure leading to this adaptation is the increased amount of land predators, such as the descendants of komodo dragons. This means that the penguins have to be more careful while exposed on land, and scouting is one method the Bald Penguins use to counter this problem.
Diving deeper
A second behavioural adaptation of the Bald Penguin the way it dives deeper during the middle of the day. This is one method employed by the Bald Penguin to escape the heat, as water at deeper depths is normally cooler than water nearer the surface. This helps the Bald Penguin cool down and prevents it from overheating. This adaptation is especially useful to the Bald Penguin, as its dorsum is a dark blue-black colour. When swimming, it is the dorsum of the Bald Penguin which is presented towards the sun. As dark colours absorb more heat than light colours, the Bald Penguin is likely to overheat faster, should it stay near the surface too long when the sun is at its highest. Therefore it is even more important that the Bald Penguin should avoid the sun as much as possible, and diving deeper underwater to darker, cooler waters when the sun is strongest is an optimal way to do it. Some environmental pressures leading to this adaptation are the great strength of the sun, as well as the fact that the water nearer the surface of the ocean is simply too hot for the Bald Penguin during the middle of the day, while water at deeper depths remain cooler.
Physiological Adaptation
Refined regurgitation
A physiological adaptation of the Bald Penguin is its refined regurgitation system for feeding its young. Like the Little Penguin, the parent Bald Penguins go hunting in the sea during daytime, eating and partially digesting the food. Upon arrival back at their burrows after dark, the Bald Penguin parents regurgitate only half of the chick's food into the chick's mouths. Enzymes in the parent penguin's stomachs keep the other half of the chick's meal relatively fresh and prevent the parent penguins from fully digesting it. The adult penguins rest during the night, and regurgitate the remainder of the chick's food before leaving the burrow. This is a useful adaptation because it allows the chicks to extract more nutrients from their food as opposed to if they just got one meal a day, mainly because they are now able to eat more. The chicks are small, and therefore their stomachs are small. The most nutrients a chick could get if it were just fed one meal a day would be the equivalent of whatever amount their stomach can hold. However, two meals mean that the chicks do not have to eat to their full stomach capacity at each meal, yet still eat more food than if they only had one meal a day. The increased amount of food means an increased amount of nutrients, which in turn means the chicks can develop faster and have more energy. An environmental pressure which gave rise to this adaptation was the increased amount of land predators. The chicks have to develop fast and have a significant amount of stored energy in case predators attack during the day, when no adult penguins are around. Although the burrows are designed so most land predators are unable to enter, burrows can collapse, and, in the event that they do, the chicks have to have the structure and the energy to help them to escape.
Modern Animal: Little Penguin
The Bald Penguin (Aquanhelo calvus), is a descendant of the Little Penguin, inhabiting the earth 50 million years from now. It has evolved sufficiently so that it is different enough from the Little Penguin to warrant a new genus, Aquanhelo, in which all penguin species are able to breathe underwater. Aquanhelo is a composite of the Latin words aqua, meaning water, and anhelo, meaning breathe. Calvus is Latin for bald. Therefore the Aquanhelo calvus is literally a bald, water-breathing penguin.
Taxonomy
Kingdom- Animalia
Phylum- Chordata
Class- Aves
Order- Sphenisciformes
Family- Spheniscidae
Genus- Aquanhelo
Species- Calvus
Diagram
Habitat
Also, the Bald Penguin inhabits the tropical areas of what is currently Australia, Papua New Guinea, and Indonesia, as shown on the distribution map. Hence, the habitat of the Bald Penguin is hot and humid, with average
The tropics, and especially the rainforest, are famous for their variety of life, and this would mean an increased amount of predators for the Bald Penguin. Some examples of predators are the descendants of snakes and the descendants of the komodo dragon. Dogs and cats also continue to threaten some colonies closer to urban areas. However, almost all of the Bald Penguin's predators live on land, as the Bald Penguin, like all penguins, are significantly less agile on land than they are in the water. All in all, this means the Bald Penguin lives in a more dangerous environment than the Little Penguin did.
The Bald Penguin continues to spend the daylight hours in the sea. The oceans of the tropics are filled with warm sea currents and plenty colourful fish. Water visibility is good, allowing the Bald penguin to easily catch its prey, fish and squid. These animals thrive in the tropics, and thus the Bald Penguin also thrives. The environment of the Bald Penguin brings it into contact with quite different animals from the ones the Little Penguin encountered. These might include the descendant of the green sea turtle and the descendant of the bellybutton nautilus. The Bald Penguin is found in tropical waters only, as it cannot withstand colder waters because of its lack of feathers.
Because of the increased number of predators associated with the rainforest environment, and the penguin's lack of agility on land, the Bald Penguin seeks to limit the time it spends on land. Therefore, the only times an adult Bald Penguin sets foot on land is to mate, or to sleep. Burrows are constructed in the sand, on the sides of cliffs, or in the undergrowth of the rainforest. These are all constructed as close to the shore as possible. Unlike their predecessors, the Bald Penguins can no longer afford a longer walk to their burrows. The Bald Penguin lives in colonies, with penguins from the same colony building burrows in the same area.
Structural Adaptations
Gill-type lungs
All penguin species in the 21st century already have a complex respiratory system, in which the air is able to travel in a circular fashion through the lungs and various sacs, as opposed to the in and out method seen in human lungs. This allows current penguins to extract as much oxygen as possible from the air, and is capable of extracting and storing massive amounts of oxygen.
Aquanhelo's lungs differ from modern-day penguin's lungs in that the inside of Aquanhelo's lungs and sacs is covered with many folded layers of tissue, looking much like a gill.
The reason why 21st century penguins (and various other animals, including humans) cannot breathe underwater is simply that the surface area of their lungs is not large enough to take in sufficient oxygen, as there is 20 times more oxygen in air than in water. However, the folded tissue in Aquanhelo's lungs and sacs give the penguin's lungs a very large surface area.
This large surface area, combined with the modern-day penguin's already advanced respiratory system means that Aquanhelo penguins are able to extract enough dissolved oxygen from water to fulfil their daily activities. Essentially, the gill-types lungs allow Aquanhelo penguins to breathe water. However, Aquanhelo penguins also retain their ability to breathe air, as their gill-type lungs are able to extract oxygen from both air and water.
Gill-type lungs is a useful adaptation for the Bald Penguin because it allows the penguin to breathe water, eliminating the need to porpoise (jump out of the water to breathe, much like dolphins or porpoises do) as the Little Penguin did. Porpoising is an activity which requires a high amount of energy, and being able to not porpoise means that the Bald Penguin is able to conserve this energy, and is therefore able to swim further, faster, deeper, and stay underwater for longer periods of time. This in turn means that the Bald Penguin is able to catch more prey than its predecessors, helping it to survive. Also, the added energy may prove useful to the Bald Penguin in escaping speedily from predators. Furthermore, in a situation that the Little Penguin was running out of oxygen, but just spied a school of fish, the Little Penguin would have no choice but to return to the surface. However, the Bald Penguin would be free to pursue the fish. This would also contribute to the Bald Penguin being able to catch more prey. An environmental pressure leading to this adaptation was the amount of time penguins spent in the sea- for hours on end, every day. In fact, the Bald Penguin probably spends more than half their life in the water. Constant porpoising to breathe is exhausting work, so the Bald Penguin developed gill-type lungs to survive in an environment where every ounce of energy is needed.
No feathers
A second structural adaptation of the Bald Penguin is its state of featherless-ness, or baldness. The featherless-ness of the Bald Penguin contributes to both its common name ("Bald" penguin) and it's Latin name (calvus is Latin for bald). This is a useful adaptation to the Bald Penguin because it prevents the penguin from overheating. The feathers of previous penguins, like the Little Penguin, had very downy bases, are unsuitable for warmer climates. In fact, there have been cases of penguins overheating on warm summer days in Antarctica, panting and lying down on the ice to try to escape the heat. If a penguin's feathers are unsuitable for a warm Antarctican day, they are definitely unsuitable for life in the tropics. The fact that the Bald Penguin is featherless means that it retains less heat, and it is easier for the Bald Penguin to cool off, thus preventing overheating. The feathers of a penguin also prevent water from reaching the penguin's skin. However, the Bald Penguin's skin is in direct contact with the water, which also helps the Bald Penguin to remain cool. Instead of feathers, the Bald Penguin's skin is much like a dolphin's, and retains the penguin's distinctive countershading (dark dorsum and light belly). The state of featherless-ness might also allow the Bald Penguin to swim faster, as, despite their waterproof-ness, the feathers of the Little Penguin might have caused the penguin some drag. The environmental pressure leading to this adaptation is the heat of the tropics, which meant that the Bald Penguin no longer needed feathers to stay warm, and is in fact in more of a danger of overheating.
Behavioural Adaptation
Scouting the shore
A behavioural adaptation of the Bald Penguin is the way they come ashore after spending a day at sea. Instead of simply waddling onto land in a group like the Little Penguin did, an entire colony of Bald Penguins congregate underwater not far from the shore. They then send two or three scouts ashore at various points of the coast. The scouts are normally slightly older penguins who have gone through at least one, more likely two or three breeding seasons. The scouts would check for predators, before calling the 'all clear' to their peers in the water, signalling that it is safe to come ashore. What follows is a mad dash by large groups of penguins to get to their burrows as fast as possible. If the all clear is not given, the colony of Bald Penguins can stay underwater all night waiting, if necessary. This is useful to the Bald Penguins because it allows them to avoid predators whenever possible, thus ensuring that the colony is not wiped out as they come ashore. The sending of scouts also allows them to minimize any damage to the colony, should there be a predator waiting for them, as only the scout would be in any danger. An environmental pressure leading to this adaptation is the increased amount of land predators, such as the descendants of komodo dragons. This means that the penguins have to be more careful while exposed on land, and scouting is one method the Bald Penguins use to counter this problem.
Diving deeper
A second behavioural adaptation of the Bald Penguin the way it dives deeper during the middle of the day. This is one method employed by the Bald Penguin to escape the heat, as water at deeper depths is normally cooler than water nearer the surface. This helps the Bald Penguin cool down and prevents it from overheating. This adaptation is especially useful to the Bald Penguin, as its dorsum is a dark blue-black colour. When swimming, it is the dorsum of the Bald Penguin which is presented towards the sun. As dark colours absorb more heat than light colours, the Bald Penguin is likely to overheat faster, should it stay near the surface too long when the sun is at its highest. Therefore it is even more important that the Bald Penguin should avoid the sun as much as possible, and diving deeper underwater to darker, cooler waters when the sun is strongest is an optimal way to do it. Some environmental pressures leading to this adaptation are the great strength of the sun, as well as the fact that the water nearer the surface of the ocean is simply too hot for the Bald Penguin during the middle of the day, while water at deeper depths remain cooler.
Physiological Adaptation
Refined regurgitation
A physiological adaptation of the Bald Penguin is its refined regurgitation system for feeding its young. Like the Little Penguin, the parent Bald Penguins go hunting in the sea during daytime, eating and partially digesting the food. Upon arrival back at their burrows after dark, the Bald Penguin parents regurgitate only half of the chick's food into the chick's mouths. Enzymes in the parent penguin's stomachs keep the other half of the chick's meal relatively fresh and prevent the parent penguins from fully digesting it. The adult penguins rest during the night, and regurgitate the remainder of the chick's food before leaving the burrow. This is a useful adaptation because it allows the chicks to extract more nutrients from their food as opposed to if they just got one meal a day, mainly because they are now able to eat more. The chicks are small, and therefore their stomachs are small. The most nutrients a chick could get if it were just fed one meal a day would be the equivalent of whatever amount their stomach can hold. However, two meals mean that the chicks do not have to eat to their full stomach capacity at each meal, yet still eat more food than if they only had one meal a day. The increased amount of food means an increased amount of nutrients, which in turn means the chicks can develop faster and have more energy. An environmental pressure which gave rise to this adaptation was the increased amount of land predators. The chicks have to develop fast and have a significant amount of stored energy in case predators attack during the day, when no adult penguins are around. Although the burrows are designed so most land predators are unable to enter, burrows can collapse, and, in the event that they do, the chicks have to have the structure and the energy to help them to escape.
Bibliography
Dargaud, G. (2010). The Penguin FAQ. Retrieved 9 July 2010, from http://www.gdargaud.net/Antarctica/PenguinFAQ.htmlHowStuffWorks. (2010). If water is made up of hydrogen and oxygen, why can't we breathe underwater?. Retrieved 9 July 2010, from http://science.howstuffworks.com/question386.htm
Penguin Anatomy- Pulmonary Anatomy. (undated). Retrieved 7 July 2010, from http://dmclf.net/biology/anatomy6.html
Translation-Guide. (2010). Free Online English to Latin Translator. Retrieved 6 July 2010, from http://www.translation-guide.com/free_online_translators.php?from=English&to=Latin
Wikipedia. (2010). Gill. Retrieved 7 July 2010, from http://en.wikipedia.org/wiki/Gill